1. Field of the Invention
The present invention relates to a filler coupling, a tap, a pressurized fluid receptacle and a filling method using such a coupling.
The invention relates more particularly to a filler coupling for a pressurized gas receptacle designed to interact with a packaging connector in order to allow said receptacle to be filled, the coupling comprising a body defining an internal filler circuit between an upstream end designed to be connected to a packaging connector and a downstream end designed to be connected to a receptacle, the coupling comprising an isolation valve that can move relative to a seat between an upstream position for closing the circuit and a downstream position for opening the circuit, said isolation valve being moved to its upstream position by a return member, the coupling also comprising a dust-prevention valve placed upstream of the isolation valve, said dust-prevention valve being able to move relative to the body between an upstream position for closing the upstream end of the circuit and a downstream position for opening the circuit upstream end, said dust-prevention valve being moved to its upstream position by a return member.
The present invention concerns in particular a filler coupling comprising in series, from upstream to downstream (in the direction of a filling with gas), a dust-prevention valve and an isolation valve.
2. Related Art
The dust-prevention valve is provided notably to form a barrier upstream of the isolation valve to prevent or limit the intrusion of particles or of dust that may damage the sealing of said isolation valve.
A removable stopper or a dust-prevention valve is usually a good protection against the intrusion of foreign bodies into a filler coupling. However, this protection is not usually sufficient because, when the dust-prevention valve is open, particles can enter during the filling operation. These particles might in certain circumstances be brought in by the filling tool that delivers the filling gas.
This contamination of the isolation valve may cause a considerable leakage rate over the life of the product on which this filler coupling is installed. This is explained by the fact that the sealing zone of the contaminated isolation valve (dust, particles etc.) loses a large proportion of its sealing capability. This risk of intrusion of particles is increased when the filler coupling is vertical (filling from above).
Another solution consists in providing a filter for solid particles in the coupling upstream of the isolation valve. This makes it possible to trap particles or dust upstream of the isolation valve but does not make it possible to actuate the opening of the isolation valve by mechanical contact (the filter in fact forming a mechanical barrier for a valve driver).
Another solution consists in providing a filter downstream of the isolation valve. This allows the mechanical actuation of the isolation valve and provides dust protection for downstream of the isolation valve (the inside of the tap and the inside of the receptacle). However, the upstream end of the isolation valve is then subject to contamination by particles or dust that can affect its sealing.